(1) Field of the Invention
The present invention relates to the removal of articles, and particularly partially packaged articles which are relatively fragile, from mandrels or cells of a package forming machine. More specifically, this invention is directed to pusher-type apparatus for imparting motion to cigarettes and especially to partially wrapped cigarette blocks which are susceptible to impact damage. Accordingly, the general objects of the present invention are to provide novel and improved methods and apparatus of such character.
(2) Description of the Prior Art
The present invention is intended for use in the packaging of cigarettes. Cigarette package forming machines typically include hollow cells or mandrels which receive preformed "blocks" of cigarettes. A paper wrapping is formed around the mandrel and folded over the bottom thereof, the wrapping being held in the closed condition after folding by means of an adhesive. In order to subsequently close the other or "head" side of the package, the cigarette blocks together with the wrapping are transferred to a head-closing mechanism, for example a head-closing turret, by means of a push-rod type ejector. In order to provide the packaging material which will be folded to form the closed head end of the package, the wrapping will extend beyond the cigarettes, i.e., at the time of transfer to the head-closing mechanism the cigarettes are set back relative to the open end of the wrapping.
An example of a prior art packaging machine with a push-rod type ejector may be seen from U.S. Pat. No. 4,476,665. In the apparatus disclosed in U.S. Pat. No. 4,476,665, each cell of a wrapping turret is provided with a ram, the "rest" position of these rams being defined and maintained by a circular guide ring. The guide ring is interrupted at the position where the partially wrapped cigarette block is to be ejected from a cell so that a reciprocal actuator may engage the ring, against which the ends of the cigarettes are already resting, and eject the partially formed package from the cell. Thus, in the apparatus of U.S. Pat. No. 4,476,665 the ram limits the receiving region of the cell. While this arrangement permits, in the case of the packaging of filter cigarettes, the filter ends to be pushed into contact with the ram when the cigarette block is loaded into the cell, it also requires that the tobacco ends be contacted in order to load the block into the cell. This contact with the tobacco ends, and the axial loading which subsequently occurs when the filter ends contact the ram during insertion, presents the possibility of damage to the cigarettes.
It is also known, for example see published German Patent application No. 2,363,108, to employ slotted cells in order to minimize the standstill time of the turret of the packaging machine. The use of a slotted cell permits the ejector device to be moved out of the transfer plane subsequent to conclusion of the pushing action. Such slotted cells, however, have the disadvantages that there is a danger the package will open before the adhesive has set and that the mechanism required to pivot the e3ector device out of the transfer plane is relatively complex and thus expensive.